Generally, a fluted casing hanger is used to support casing inside a wellhead. The annulus between the outside of the fluted casing hanger and the inside of the wellhead must be sealed off. Generally, it is old to use a resilient squeeze-type sealing element that is locked into the annulus and squeezed into a sealing relationship. However, generally such seal assemblies have had disadvantages such as being energized by making up threads that have to be engaged remotely, which is difficult when drilling from a floating vessel, or require left-hand rotation for removing the seal assembly which is an undesired operation in a drilling string.
The present invention is directed to an improved locking assembly for securing a seal assembly or other well members in or on a tubular well member having a locking notch. The present invention is also directed to various improvements in a seal assembly in which (1) all operations are performed with a push, pull or right-hand rotation, (2) eliminates all operations requiring left-hand rotation, (3) no threads are required to be engaged or disengaged remotely, (4) the parts are secured together by a limited longitudinal lost motion connection eliminating the possibility of parts of the assembly coming apart while it is being installed or retrieved, (5) the seal assembly may be locked on to the wellhead or onto the casing hanger, (6) the seal assembly is designed to give an actual pressure test of the seal without loading of the seal element by the running tool during the test, and (7) the actuation of the resilient seal is performed by a non-threaded energy connection for imparting rotation thereto.